Coking stoker



Aug. 10, 1965 E. C. MILLER COKING STOKER Original Filed Jan. 5, 1960 INVENTOR. Earle C. ZZ ZeT UnitedStates Patent O 3,266,049 l l CIGNG STQKER Earle C. Miller, Worcester, Mass., assignor to Riley Stoller Corporation, Worcester', Mass., a corporation of Massachusetts Continuation of application Ser. No. 588, Jan. 5, 1960. T his application July 17, 1962, Ser. No. 211,944 2 Ciaims. (Cl. 202--117) This invention relates to a coking stoker and more particularly to apparatus arranged to produce coke by partial combustion of coal. This is a continuation of my patent application lSerial Number 588, tiled January -5, 1960, and now abandoned. y l

In the production of coke for use in metallurgical processes it has been proposed to produce this coke by partially burning coal on a traveling grate. This procedure has been fairly successful, but certain difficulties have been experienced. For one thing, the quality of the coke produced by this method is not as high as that produced by certain well-known batch methods, such as the beehive process. Another diiiculty is that the coke, as it leaves the traveling grate, is quite hot and is difficult to handle. These and other difficulties experienced with the prior art devices have been obviated in a novel manner by the present invention.

It is, therefore, an outstanding object of the invention to provide a coking stoker which will produce a relatively cool coke which is readily handled.

Another object of this invention is the provision of a coking stoker which will produce coke of as good a quality as beehive and other batch coke processes.

A further object of the present invention is the provision of a coking Stoker in which the coke is quenched in a dry state, which condition is quite desirable from the standpoint of theultimate use of the coke and the handling thereof.

It is another object of the instant invention to provide a traveling grate coking Stoker in which the discharge end of the grate does not become overheated.

With these and other objects in view, as will be apparent to those skilled in the art, the invention resides in the combination of parts set forth in the speciication and covered by the claims appended hereto.

The character of the invention, however, may be best understood by reference to certain of its structural forms as illustrated by the accompanying drawing in which:

The single gure shows a vertical sectional View longitudinally of an apparatus embodying the principles of the present invention.

Referring to the drawings, the coking Stoker, indicated generaly by the reference numeral 1t), is shown as comprising a furnace 11 having a combustion chamber 12 which is of a generally vertically-elongated form. At its upper end the combustion chamber is provided with an outlet 13 through which gases pass flowing to a heatadsorbing apparatus, such as a boiler 14. The boiler is provided with a steam-and-water drum 15 from which extend downcomer tubes 16 and steam-release tubes 17. A superheater 18 lies adjacent the outlet 13, which outlet also lies adjacent an inlet 19 of the boiler 14. The boiler 14 is provided with an outlet 21 which is connected to a back pass 22 which, in turn, is connected through a fan 23 to a breaching 24 leading to a stack (not shown). Underlying the combustion chamber 29 is an endless-chain traveling grate 25 which is driven so that its upper run moves rearwardly toward a hopper 26 which is located in an area underlying the boiler 14; an arch 27 closely overlies the discharge end of the grate 25 and also overlies the hopper 26. Mounted on the front wall of the furnace 11 is a feeder hopper 28 serving to provide fresh coal to the traveling grate at a pre- 2 determined rate. Underlying the upper run of the grate 2S are a series of vertical Walls defining air Zones 29 which constitute compartments into which air is fed originating in a force draft fan 31.k Each air zone is individually adjustable by dampers (not shown). Overre air nozzles 32 and '33 are also furnished withair from the fan 31 and a damper 34 regulates'the flow of air thereto. The discharge end ofthe grate 25 is provided lwith gas Zones 35, Sdand 37 which are separated from each other and from the Vair Zones 29and are connected by ducts 38, 39, and 41, respectively, *to a gas box 42. A duct 43 connects the-gas box 42 to the outlet of a yfan 44, the inner end of which is connected to the breaching 24 just past the induced draftffan 23. Located in the duct 43 is a damper 45 which is actuated through levers. bya hydraulic linear actuator 46 which actuator receives its hydraulic fluid from a control 47 of a well-known type. The control receives an electrical signal through a line 4S from a thermocouple 49 located just under the surface of the upper run of chain of the traveling grate 25 between the gas Zones 36 and 37.

The operation of the apparatus will now be readily understood in view of the above description. Coal is delivered to the feeder hopper 23 and is delivered to the surface of the upper run of the traveling grate 2S. It then moves across the bottom of the combustion chamber 12. Air from the zones 29 passes upwardly through the coal; the volatiles in the coal are driven upwardly and burn in the combustion chamber. After complete distillation and combustion of the volatiles the products of combustion pass through the outlet 13 of the combustion chamber over the superheater 18 and through the inlet 19 of the boiler. The products of combustion thus pass into the boiler 14 and, after passing over the steam release tubes 17 and the downcomer tubes 15 in the usual manner, they leave the boiler by means of the outlet 21. The gas is then passed downwardly through the back pass 22, through the induced draw fan 23, and through the breaching 24 of the stack. The coal from which the volatiles have been driven is passing in the meanwhile rearwardly along the traveling grate Stoker 25 toward the hopper 26. The coke at this time is in an incandescent condition and is very diicult to handle. Furthermore, as the discharge end of the grate is approached the danger of the grate elements overheating, burning, and being destroyed becomes increasingly greater. For that reason, the fan 44 removes some of the cooled products of combustion from the breaching 24 and passes them through the duct 43 and the ducts 38, 39 and 41 into the gas zones 35, 36, and 37, respectively. The ow of gases into these zones and through the coke is regulated by means of dampers and the net effect is to cool the coke because the combustion gases by the time they have reached the breaching 24 are much cooler than the coke itself and certainly much cooler than the gases which originally left the combustion chamber. In this way, the coke is heated, cooled, and falls into the hopper 26 where it is easily handled. At the same time, the grates of the traveling grate 25 are in no danger of overheating. As a matter of fact, the thermocouple 49 gives a continuous signal through the line d8 to the control 47. This, in turn, regulates the amount of gas which is returned to the grate. When the grate elements appear to be hotter, as measured by the thermocouple 49, the damper 45 will be opened further to permit more gas to flow through the grate and the coke.

It is obvious that minor changes may be made in the form and construction of the invention without departing from the material spirit thereof. It is not, however, desired to confine the invention to the exact form herein shown and described as is desired to include all such as properly come within the scope claimed.

aeoaoae .E The invention having been thus described, what is claimed as new and desired to secure by Letters Patent is:

l. A coking Stoker, comprising a furnace having a combustion chamber with an outlet at the upper end, a traveling grate underlying the chamber at the lower end and having an arch overlying the discharge end, a heatabsorbing apparatus associated with the furnace and hav- Ving an inlet connected to the outlet of the chamber to receive hot products of combustion therefrom, the heatabsorbing apparatus having an outlet to discharge the said products of combustion at a lower temperature, vertical walls defining air compartments located under a substantial portion of the grate, a gas compartment located I 4 for control by the thermocouple for regulating the amount of products-of combustion so introduced.

Z. A coliing Stoker as recited in claim 1, wherein the said duct is provided with a damper whose setting is regulated by the said control means, the duct being connected to the gas compartment by a plurality of connecting `ducts each of which is provided with a separatelyadjustableV damper.

References Cited by the Examiner UNITED STATES PATENTS 3,013,951 12/61 Manseld 202-117 X FOREGN PATENTS 655,257 12/28 France.

Monats o. woLK, Prr'rrmry Examiner. DELBERT E. GANTZ, Examiner.v 

1. A COKING STOKER, COMPRISING A FURNACE HAVING A COMBUSTION CHAMBER WITH AN OUTLET AT THE UPPER END, A TRAVELING GRATE UNDERLYING THE CHAMBER AT THE LOWER END AND HAVING AN ARCH OVERLYING THE DISCHARGE END, A HEATABSORBING APPARATUS ASSOCIATED WITH THE FURNACE AND HAVING AN INLET CONNECTED TO THE OUTLET OF THE CHAMBER TO RECEIVE HOT PRODUCTS OF COMBUSTION THEREFROM, THE HEATABSORBING APPARATUS HAVING AN OUTLET TO DISCHARGE THE SAID PRODUCTS OF COMBUSTION AT A LOWER TEMPERATURE, VERTICAL WALLS DEFINING AIR COMPARTMENTS LOCATED UNDER A SUBSTANTIAL PORTION OF THE GRATE, A GAS COMPARTMENT LOCATED UNDER THE DISCHARGE END OF THE GRATE, A DUCT CONNECTING THE OUTLET OF THE HEAT-ABSORBING APPARATUS TO THE GAS COMPARTMENT, A FAN IN THE DUCT FOR INTRODUCING PARTIALLYCOOLED PRODUCTS OF COMBUSTION THROUGH THE GRATE AND THROUGH THE COKE, A THERMOCOUPLE LOCATED ADJACENT THE DISCHARGE END OF THE GRATE, AND MEANS LOCATED IN THE DUCT FOR CONTROL BY THE THERMOCOUPLE FOR REGULATING THE AMOUNT OF PRODUCTS OF COMBUSTION SO INTRODUCED. 